Cold temp primers

[Chris Butler]

Is there any conclusive evidence for using magnum primers in a small bore non-magnum cartridge in cold temps, i.e. single digits? Specifically .223 Rem bolt gun

 

[M-61]

Not from me. Maybe I'm one of the few (I don't know) but primers over ALL these years (seating etc.) I'd say have been the least of my problems by far. And I have shot in some horribly cold places.

 

[mikecr]

You should stick with the primers that you load developed with. For colder temps intended you might plan on developing with thinner primers (Feds, Wins). This, because striking often slows with dropping temps and thicker primer cups (like with CCIs) become susceptible to misfiring first.

 

[Chris Butler]

you might plan on developing with thinner primers (Feds, Wins).

Thanks much!

 

[Dusty Stevens]

Is there any conclusive evidence for using magnum primers in a small bore non-magnum cartridge in cold temps, i.e. single digits? Specifically .223 Rem bolt gun

You should actually look for a thinner cup like they said above. A magnum primer does not contain hotter compound or whatever, it has the thicker cup to contain magnum pressures

 

[brokeasajoke]

CCI claims 23% hotter flame and longer flame duration on magnum primers per their website (I just looked) . I use magnum on my 223 loads for my ARs.
https://www.cci-ammunition.com/products/primers/primers.aspx?id=29

 

[mongo chicago]

Some powders, like Win. ball powders require magnum primers because of the heavy coating on them. But that is in all temps.

 

[jepp2]

A magnum primer does not contain hotter compound or whatever, it has the thicker cup to contain magnum pressures

I thought they did, but it is probably just me.

Anyway, recognize there is a LOT of difference in primer energy between different brands. You might enjoy seeing the results of this study:

http://www.6mmbr.com/primerpix.html

 

[Laurie]

In 308 Win Palma brass, there was only an 18 fps average MV spread on MVs of ~2,820 fps over 14 SR primer models in my tests here:

http://www.targetshooter.co.uk/?p=2662

Magnum / BR models were spread evenly throughout the speed spectrum. As Dusty says, there is no correlation between magnum and pressure / speed in the SR size.

 

[Chris Butler]

You should actually look for a thinner cup like they said above.

Thank You!
I ordered some Federal small rifle and small rifle match post haste.

 

[dkhunt14]

I thought the 223 required the thicker cups to keep from blanking them. I remember reading where guys used Remington 7 1/2 and CCI BR4 because of pressure. Matt

 

[Webster]

Is there any conclusive evidence for using magnum primers in a small bore non-magnum cartridge in cold temps, i.e. single digits? Specifically .223 Rem bolt gun

Interesting article on primers.

http://www.the-long-family.com/primer_study.htm

 

[Chris Butler]

Thank You

 

[p-man]

I don't think that one primer brand is categorically going to be better than another in lower relative temperatures - the largest and most significant variable will always be the powder; with all the tests done rating "heat of brisance" and related pressure and velocity results, I've never seen any evidence that inconsistent results in velocity or accuracy at lower temps could be traced to differing primer 'performance'. Most primers generate flash temp of 900 degrees F give or take, so changes in relative air temps - of say 40 degrees - is not going to change primer function. Having said that, Winchester Large Rifle primers tend to generate larger 'flash' particles that penetrate deeper into larger powder charges than other brand/types, so if you want to ensure the most complete powder ignition under any conditions that would be my choice. How accurate (consistent) the WLR primer would be with your powder/bullet combination is a whole different story. All that IMHO

The main difference in regular rifle primers and magnum rifle primers is not in the heat or duration of flash but in the construction of the primer body. Magnum primers are built of heavier (thicker) walls to help withstand deformation of the primer cup from the higher pressures generated within the cartridge case during ignition. That being the case, Winchester larger and magnum primers appear to be constructed identically, and once when I compared chronographed Win 270 velocities between the two with identical components using I-4350, I could not see discernable differences nor was one more accurate than the other. So I stick to my belief if my pet load at 70 degrees goes s--t at 30 degrees, it ain't the primer that's the issue. YMMV

 

[mongo chicago]

Have to disagree with p-man. Decades ago, I saw some photos when they were testing regular and magnum primers. The magnum primers DEFINITELY had a much brighter/hotter flash.

 

[JRS]

Remington 7 1/2

 

[JRS]

CCI BR4

 

[Zero333]

I shoot in cold temps. - 20 Celsius. I've had duds with BR2 primers, but NEVER with 210m primers.

Br2 primers have a harder cup than 210m. I don't think it's a coincidence.

 

[p-man]

And I must defer to you on that - I have no idea what it's like to shoot at those temperatures. If you've tried all the major manufacturers' primers, is it your experience that all magnum primers shoot more consistently than regular large rifle primers?

 

[fivering1]

You should actually look for a thinner cup like they said above. A magnum primer does not contain hotter compound or whatever, it has the thicker cup to contain magnum pressures

Incorrect! Read up on studies done on different primers.